New Concept

[mark0491]

hi i was thinking of making this it would be my second one to use air .

it would use 4 individual small tanks and to use them you'd open one ball valve. to fire would be a modified QEV.

It will be pump action with a Bolt action setup the barrel will be roughly 1.5 foot long . this is ment to be used fast and repetitive and compact for the chambers im probably going to use 2'' x1' and the barrel 1''x1.5'

[Pete Zaria]

No real "new" concepts here, just throwing together a few existing concepts... should work fine.

You only need one fill valve. Open all the ball valves for the chambers, pump the entire thing upto whatever PSI, then close all the ball valves. Open them one at a time as planned...

Add a pressure gauge.

Using multiple chambers does work, but always increases dead space and bulkiness. I'd consider running the chambers horizontally instead of vertically, and use them as a butt-stock of sorts.

An over/under configuration would make your pump action loader just a little bit harder to built, but would allow for a "bullpup" style design with a longer barrel.

If you're going to all this work, why not make a simple gravity-fed magazine for that breech loader....?

I assume you meant modified sprinkler, not modified QEV? A 1.5" sprinkler valve, modded right, should be fine for this.

Good luck!

Peace,
Pete Zaria.

[Fnord]

Couldn't you use one big chamber, one small secondary chamber, and maybe a regulator?

OR
You could try making self contained cartridges. neither of these ideas are really new concepts though.

I have an unfinished gun sitting on my pinic table that uses the same concept, though it's a bit bigger. I was going to enter it in the competition but I figured I'd have a better chance of getting the hybrid done in time.
(I'll post pictures if you really want me too... kinda lazy right now).

Ok, I posted it, but the colors are a little funky.
Rather than explaining everthing in this post, I made a diagram showing the basic setup and how the valve works.
And before anyone asks, this gun uses custom pvc plugs instead of 3" endcaps.

[trae08]

POST PICTURES OF IT. id like to see it

[mark0491]

true about the one fill valve i want to keep this as small as a semi sawed of shot gun...... One of the "tanks" is the stock. and the other tree are straight.
and yes i did mean sprinkler valve.

[Pete Zaria]

I'd still go with a bullpup-type design, to allow for a longer barrel in an overall smaller package. Have a U bend at the end of the chambers, connected to the barrel (which runs over the top of the chambers), with the pump action mechanism mounted under the barrel, right infront of the chambers (hope that makes sense).

Cool project. Best of luck.

Peace,
Pete Zaria.

[mark0491]

the point was not to have a long barrel because it is not really for accuracy. i mean bullpups are cool and all by it make the air have a longer travel distance. any ways when i get some money this baby's going to be awesome

[Flying_Salt]

Pete's first post gave me an idea, maybe you can fire it an extra time by using the elbows and stuff that connect them as a chamber. Maybe you can make an 8-chambered thing that looks like an octopus and shoots water

[MrCrowley]

When you open the ball valve to another chamber after the first initial shot the sprinkler valve will take a bit of pressure to seal and it will leak some out so on top of losing pressure to dead space you will also lose some sealing the valve.

[spud yeti]

Its going to be a mission to pump up each chamber individually, having to take off the pump every time. you should create something like this (Its detachable): http://s203.photobucket.com/albums/aa95 ... =idea2.jpg
But you would have to make pins in each of the inlets to open the schrader valves, like this: http://s203.photobucket.com/albums/aa95 ... eazoom.jpg
This is just an idea though.
Otherwise the design looks pretty good.